There are many cases where a hole that has been carelessly created in a plate causes a problem.
For example, each of the four walls (plates) 2, 2, 2, and 2 that form a box for wiring in Patent Document 1 or a well-known outlet box 1 shown in FIGS. 1 and 6 in the present application is provided with a number of holes 3, 3, . . . 3 of which the sizes are different for connecting a wire pipe, and all of the holes 3 for connecting a wire pipe are respectively provided with a blind cover in proximity to the inner periphery 5 in such a state that the blind cover is linked to inner periphery of each hole 3, as shown in FIGS. 1 and 6, with microscopic linking portions 6 (points of attachment) so that detachment and separation are easy.
Thus, the holes 3 for connecting a wire pipe can be respectively covered by a blind cover so that bugs and the like can be prevented from entering the box 1. Meanwhile, in the case where a wire pipe is connected to the box 1, a blind cover 4 can be easily removed in a well-known manner so that a hole 3a for connecting a wire pipe is opened, which makes it easy to connect a wire pipe through the hole 3a. 